Michael Papazian

This dissertation is an examination of the role of intuition and truth in the development of theories of rationality. Reliance on intuitions in the formation of such theories has been criticized. In an effort to determine whether these criticisms are valid, I devote the first chapter to an examination of the concept of intuition. I discuss the historical background of the modern concept of intuition. I then discuss the account of intuition offered by L. Jonathan Cohen. After showing how Cohen's account can be improved, I argue that although intuitions have a role in the development of theories of rationality, they are not the main source of the norms of reasoning. I then apply my discussion of intuition to an argument of Cohen's purporting to establish that human irrationality cannot be empirically demonstrated. I argue against a number of criticisms of Cohen's argument, but then present my own reasons why Cohen's argument fails. ;In the second chapter, I turn my attention to an argument of Stephen Stich's. Stich has argued that we should not use a truth-based criterion as the standard of rationality. Stich argues that semantic theories essentially rely on appeals to intuition, and that since appeals to intuition are inherently conservative, valuing semantic concepts, such as truth, leads to a conservatism. I argue that semantic theories do not rely on intuitions, and that even if appeals to intuitions are made in the construction of such theories, the consequences against which Stich warns would not follow. ;I proceed in the third and final chapter to examine what role truth should have as epistemic virtue in a naturalistic epistemology. I argue that a thoroughgoing pragmatic epistemology that eschews truth is implausible. But I argue that truth-based accounts of justification and rationality which make truth the principal epistemic value are also implausible. Such accounts ignore relevant psychological evidence that indicate that truth can only be one of many epistemic virtues for us. I end by arguing that theories of rationality must recognize a plurality of epistemic virtues

One of the most intriguing claims of Stoic logic is Chrysippus's denial of the modal principle that the impossible does not follow from the possible. Chrysippus's argument against this principle involves the idea that some propositions are ?destroyed? or ?perish?. According to the standard interpretation of Chrysippus's argument, propositions cease to exist when they are destroyed. Ide has presented an alternative interpretation according to which destroyed propositions persist after destruction and are false. I argue that Ide's alternative interpretation as well as some versions of the standard interpretation conflict with Stoic doctrines about the nature of propositions. I propose another version of the standard interpretation based on Frede's account of the Stoic theory of the proposition. I hold that this version of the standard interpretation both escapes Ide's objections and is consistent with Stoic logic and philosophy of language.

Meijer's book, a comprehensive study of Stoic theological arguments, defends the thesis that the Stoics were not narrowly interested in proving the existence of a god. The theology of the Stoa began with its founder, Zeno of Citium, presenting arguments that the cosmos is an intelligent being, though Zeno himself seems not to have explicitly identified that intelligent being as god. A clear statement equating the cosmos with god had to wait until the rise of the third head of the school, Chrysippus, though Meijer acknowledges that there is no reason to think that Zeno or Cleanthes, the second head, would have opposed the proposition that the cosmos, or at least the rational fire that pervades it, is god. Confusion about the true intent of Zeno's arguments is due to their distortion in the sources, for example, by Sextus Empiricus, who, Meijer contends, presents several of Zeno's arguments for the rationality of the cosmos as if they were intended as arguments to establish the existence of god. As a result, Sextus is an unreliable witness for determining the point of these arguments. Further confusing matters is the existence of a set of arguments attributed to Zeno that aim to establish the existence of the traditional gods. Meijer

The Stoic philosopher Chrysippus wrote extensively on the liar paradox, but unfortunately the extant testimony on his response to the paradox is meager and mainly hostile. Modern scholars, beginning with Alexander Rüstow in the first decade of the twentieth century, have attempted to reconstruct Chrysippus? solution. Rüstow argued that Chrysippus advanced a cassationist solution, that is, one in which sentences such as ?I am speaking falsely? do not express propositions. Two more recent scholars, Walter Cavini and Mario Mignucci, have rejected Rüstow's thesis that Chrysippus used a cassationist approach. Each has proposed his own thesis about Chrysippus? solution. I argue that Rüstow's view is fundamentally correct, and that the cassationist thesis gains greater plausibility when viewed in light of a passage in Sextus Empiricus? Adversus mathematicos that the previous commentators have ignored, and when understood within the broader context of Stoic logical theory and philosophy of language. I close with a brief remark on the significance of Chrysippus? work for the modern debate on the semantic paradoxes.

An argument for the existence of gods given by the Stoic Diogenes of Babylon and reported by Sextus Empiricus appears to be an ancient version of the ontological argument. In this paper I present a new reconstruction of Diogenes' argument that differs in certain important respects from the reconstruction presented by Jacques Brunschwig. I argue that my reconstruction makes better sense of how Diogenes' argument emerged as a response to an attack on an earlier Stoic argument presented by Zeno of Citium. Diogenes' argument as reconstructed here is an example of a modal ontological argument that makes use of the concept of being of such a nature as to exist. I argue that this concept is a modal concept that is based on the Philonian definition of possibility, and thus that Diogenes' argument is a source of important evidence about the use of non-Stoic modalities in the post-Chrysippean Stoa. I conclude by arguing that the objections made against considering Diogenes' argument as ontological are unfounded and that Diogenes' argument clearly resembles modern versions of modal ontological arguments